HP StorageWorks Enterprise File Services WAN Accelerator 3.0.4 Management Console user guide (AG421-96002, March 2007)

42 CONFIGURING THE HP EFS WAN ACCELERATOR
5. Click Save to save your settings permanently or click Reset to return the settings
to their previous values.
Enabling
HSTCP Protocol
Options
You enable the High Speed Transmission Control Protocol (HSTCP) in the
Optimization Service - Protocol: HSTCP page.
HSTCP provides acceleration and high throughput for high bandwidth networks where
the WAN pipe is large but latency is high. HSTCP is activated for all connections that
have a Bandwidth-Delay Product (BDP) larger than 100 packets. HSTCP is available
only on the Series 5000.
To configure HSTCP you must perform the following tasks.
Add New Volume Configuration FSID. Specify the file system identification number (ID) to add a new NFS volume.
Policy. Select one of the following options from the drop-down list to configure the
policy for NFS volumes:
Global Read-Write. Specifies a policy that provides a trade-off of performance for
data consistency. All of the data can be accessed from any client, including LAN based
NFS clients (which do not go through the HP EFS WAN Accelerators) and clients
using other file protocols like CIFS. This option severely restricts the optimizations
that can be applied without introducing consistency problems. This is the default
configuration.
Custom. Enables you to turn on or off the root squash feature for NFS volumes from
this server.
Home Directory. All accesses to each directory are by a single user. This policy allows
aggressive caching of data and metadata.
Enable Root Squash. Select this option to enable root squashing.
Add Volume. Click Add Volume to add the NFS volume to the list.
Remove Selected Volumes. To remove an entry, click the check box next to the name
and click Remove Selected Volumes.
Control Description
Task Description
Enable HSTCP support. For detailed information, see “To enable HSTCP protocol support” on page 43.
Increase the WAN buffers. Increase the WAN buffers to 2 Bandwidth Delay Product (BDP) or 10 MB. For
detailed information, see “To enable HSTCP protocol support” on page 43.
You can calculate the BDP WAN buffer size. For example, for a link of 155
Mbps and 100 ms round-trip delay, the WAN buffers should be set to:
2 * 155 Mbps * 100 ms = 3875000 bytes
Increase the LAN buffers. Increase the LAN buffers to 1 MB. For detailed information, see “To enable
HSTCP protocol support” on page 43.